michael@0: /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.widget;
michael@0: 
michael@0: import android.content.Context;
michael@0: import android.graphics.Canvas;
michael@0: import android.graphics.Matrix;
michael@0: import android.graphics.drawable.Drawable;
michael@0: import android.util.AttributeSet;
michael@0: import android.widget.ImageView;
michael@0: 
michael@0: /* Special version of ImageView for thumbnails. Scales a thumbnail so that it maintains its aspect
michael@0:  * ratio and so that the images width and height are the same size or greater than the view size
michael@0:  */
michael@0: public class ThumbnailView extends ImageView {
michael@0:     private static final String LOGTAG = "GeckoThumbnailView";
michael@0:     final private Matrix mMatrix;
michael@0:     private int mWidthSpec = -1;
michael@0:     private int mHeightSpec = -1;
michael@0:     private boolean mLayoutChanged;
michael@0: 
michael@0:     public ThumbnailView(Context context, AttributeSet attrs) {
michael@0:         super(context, attrs);
michael@0:         mMatrix = new Matrix();
michael@0:         mLayoutChanged = true;
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onDraw(Canvas canvas) {
michael@0:         Drawable d = getDrawable();
michael@0:         if (mLayoutChanged) {
michael@0:             int w1 = d.getIntrinsicWidth();
michael@0:             int h1 = d.getIntrinsicHeight();
michael@0:             int w2 = getWidth();
michael@0:             int h2 = getHeight();
michael@0:     
michael@0:             float scale = (w2/h2 < w1/h1) ? (float)h2/h1 : (float)w2/w1;
michael@0:             mMatrix.setScale(scale, scale);
michael@0:         }
michael@0: 
michael@0:         int saveCount = canvas.save();
michael@0:         canvas.concat(mMatrix);
michael@0:         d.draw(canvas);
michael@0:         canvas.restoreToCount(saveCount);
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
michael@0:         // OnLayout.changed isn't a reliable measure of whether or not the size of this view has changed
michael@0:         // neither is onSizeChanged called often enough. Instead, we track changes in size ourselves, and
michael@0:         // only invalidate this matrix if we have a new width/height spec
michael@0:         if (widthMeasureSpec != mWidthSpec || heightMeasureSpec != mHeightSpec) {
michael@0:             mWidthSpec = widthMeasureSpec;
michael@0:             mHeightSpec = heightMeasureSpec;
michael@0:             mLayoutChanged = true;
michael@0:         }
michael@0:         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
michael@0:     }
michael@0: }